The use of hypodermic needles subjects the user to considerable risk of contracting a disease or disorder in the event the user pricks his or her finger following use of the hypodermic needle on such other person. In like manner, the person upon whom the hypodermic needle is used by another person is subjected to the same risk if the user has a communicable disease and pricks his or her finger prior to use of the needle.
The prior art contains many proposals for protecting the users of hypodermic needles against inadvertent pricking by the needle. Some of the proposals have included flexible or collapsible covers which overlie the needle, others have included shields or guards which encircle the needle, and still others comprise pads in which the top of the needle may be embedded. Most, if not all, of the known protective devices require manipulation of the shield or guard by the hands of the user and in such manner that the user's fingers must pass very close to the needle tip, thereby exposing the user to the risk of being pricked by the needle. The exposure to risk is increased in those instances in which the shield is flexible, or collapsible, or consists simply of a pad of spongy material.
Protective devices constructed in accordance with the invention overcome the disadvantages referred to above by utilizing relatively rigid shields of such size as to accommodate not only the entire needle, but also a substantial portion of the syringe from which the needle projects. The length of the shield and its rigidity make possible placement of the user's fingers on the shield in an area remote from the tip of the needle. The rigidity of the shield minimizes greatly the risk that the needle will penetrate the shield as the latter is applied to or removed from the syringe. Finally, the shield is latched in its protective position, thereby minimizing the possibility of inadvertent exposure of the needle. The shield may be released from its latched, protective condition either by relative rotation of the shield and the syringe or by deflection of the latching part of the shield.